I need hardly remind you of the complexity of the subject I intend to handle. Subtler minds and abler pens than mine have been brought to the task of unravelling the mysteries of Caste; but unfortunately it still remains in the domain of the “unexplained,” not to say of the “un-understood.” I am quite alive to the complex intricacies of a hoary institution like Caste, but I am not so pessimistic as to relegate it to the region of the unknowable, for I believe it can be known. The caste problem is a vast one, both theoretically and practically. Practically, it is an institution that portends tremendous consequences. It is a local problem, but one capable of much wider mischief, for “as long as caste in India does exist, Hindus will hardly intermarry or have any social intercourse with outsiders; and if Hindus migrate to other regions on earth, Indian caste would become a world problem.”² Theoretically, it has defied a great many scholars who have taken upon themselves, as a labour of love, to dig into its origin. Such being the case, I cannot treat the problem in its entirety. Time, space and acumen, I am afraid, would all fail me, if I attempted to do otherwise than limit myself to a phase of it, namely, the genesis, mechanism and spread of the caste system. I will strictly observe this rule, and will dwell on extraneous matters only when it is necessary to clarify or support a point in my thesis. ² Ketkar, _Caste_, p. 4. To proceed with the subject. According to well-known ethnologists, the population of India is a mixture of Aryans, Dravidians, Mongolians and Scythians. All these stocks of people came into India from various directions and with various cultures, centuries ago, when they were in a tribal state. They all in turn elbowed their entry into the country by fighting with their predecessors, and after a stomachful of it settled down as peaceful neighbours. Through constant contact and mutual intercourse they evolved a common [pg 82] culture that superseded their distinctive cultures. It may be granted that there has not been a thorough amalgamation of the various stocks that make up the peoples of India, and to a traveller from within the boundaries of India the East presents a marked contrast in physique and even in colour to the West, as does the South to the North. But amalgamation can never be the sole criterion of homogeneity as predicated of any people. Ethnically all peoples are heterogeneous. It is the unity of culture that is the basis of homogeneity. Taking this for granted, I venture to say that there is no country that can rival the Indian Peninsula with respect to the unity of its culture. It has not only a geographic unity, but it has over and above all a deeper and a much more fundamental unity—the indubitable cultural unity that covers the land from end to end. But it is because of this homogeneity that Caste becomes a problem so difficult to be explained.